Long cranking when starting after sitting

[jagchick]

Like many of you, my 98 goes through a long cranking scenario before it decides to start. A mechanic replaced the starter and I replaced the spark plugs and wires, fuel pump and FPR. I got no reaction out of any of these except slightly quicker starts from replacing the FPR, but not perfect. The dealer said there was a pressure leak from the brand-new fuel pump, but I don't think that could be, since I replaced it a few weeks ago (the other one was said to have a pressure leak, but I think it was fine too). Could this be a simple gas cap gone bad? I know the SES light should come on if the cap has been left off, but perhaps there is a slow leak in the cap. Where else could pressure be leaking except the FPR and gas tank?

[dlistro]

did you do a fuel pressure test? Pressure should be between 41 and 47 psi.

[Indy8]

The fuel tank is not under pressure as related to the fuel pressure to the engine. The slight release you hear when unscrewing the gas cap is part of the vapor recovery system for emissions regulations.

[jagchick]

Originally Posted by dlistro

did you do a fuel pressure test? Pressure should be between 41 and 47 psi.

Thank you. The mechanic did a pressure test and said the system holds pressure until the car is turned off, then it leaks pressure. He was sure it was leaking at the fuel pump, so I replaced it and now the dealership said it still leaks at the pump (I don't know exactly how they determine it's the pump, that's why I suspected that it is leaking somewhere else in the gas tank). I do not have a pressure guage. Are you sure a faulty gas cap cannot cause a pressure leak?

[BigRedAurora]

you could be loosing pressure through LEAKY FUEL INJECTORS.

[Indy8]

You know what???... I bet it's a bad gas cap!

[corning_d3]

Faulty fuel pressure regulator..Maybe?

[Indy8]

Originally Posted by corning_d3

Faulty fuel pressure regulator..Maybe?

Did you not even read the first post?

[corning_d3]

Ever had new parts fail?

[jagchick]

Well shoot, the new gas cap made no difference. A new FPR did help with the long cranking, but it's still not 100%. There must be something else contributing to it. Usually it would start up right away first thing in the morning, and only do the long-cranking thing after it had sat for 30+ minutes after being driven. But now after replacing the FPR, it gets crabby in the morning but starts better later throughout the day. What are the chances that my new fuel pump is bad? Especially when it works just as well as my old one (which didn't make any wierd noises or do anything wacky while driving)? I think it's something besides the fuel pump and FPR.

[GuMan]

I had this problem, and I went through 2 FPR installs before I did it
myself and fixed this. The FPR is easy to screw up during install.

What happened to me was that whenever the car was warm enough
to not need a rich mixture, and it had sat for at least 15-20 minutes
it would act like yours.

The FP is modulated by engine vacuum through a vacuum hose
attaching to just behind the throttle plate. If you pull this off
and find that there is moist or wet gas in there, you have a cracked
FPR diaphram, or at least on where the edge lifted up when it was
replaced. If the whole FPR was replaced as a component, then I
don't know how that could of happened. But.. it is easy to check.

What happens is that fuel leaks into the manifold when you are
shut down. If your engine is warm enough to not want a rich
mix, it won't start until you pump enough air through the manifold
and vapor off the extra fuel laying about. Once I replaced my FPR
myself (not the dealer, who screwed it up twice) it worked like a champ.

Hope this helps,
GuMan